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Halitpaşa Transpressive Zone: Implications For An Early Pliocene Compressional Phase In Central Western Anatolia, Turkey, Orhan Kaya, Engi̇n Ünay, Gerçek Saraç, Silke Eichhorn, Sabine Hassenrück, Andrea Knappe, Asaf Pekdeğer, Serdar Mayda Jan 2004

Halitpaşa Transpressive Zone: Implications For An Early Pliocene Compressional Phase In Central Western Anatolia, Turkey, Orhan Kaya, Engi̇n Ünay, Gerçek Saraç, Silke Eichhorn, Sabine Hassenrück, Andrea Knappe, Asaf Pekdeğer, Serdar Mayda

Turkish Journal of Earth Sciences

The Late Cenozoic evolution of the eastern Aegean is dominated by widespread continental extension. The most prominent structures are E-W- and NE-SW-trending grabens and intervening horsts, while NW-SE- and N-S-trending faults form the other less important structures. This paper documents the results of recent geological mapping and structural and stratigraphical analysis from the Halitpaşa half graben, which forms the northwestern continuation of the Gediz Graben. Field evidence for a new NW-SE-trending dextral wrench-dominated fault zone (here named the Halitpaşa transpression zone), which involved the thrusting of pre-Palaeogene basement onto Upper Miocene-Lower Pliocene sediments, is presented. The fault zone is correlated …


The Problem Of The Core-Cover Boundary Of The Menderes Massif And An Emplacement Mechanism For Regionally Extensive Gneissic Granites, Western Anatolia (Turkey), Burhan Erdoğan, Tali̇p Güngör Jan 2004

The Problem Of The Core-Cover Boundary Of The Menderes Massif And An Emplacement Mechanism For Regionally Extensive Gneissic Granites, Western Anatolia (Turkey), Burhan Erdoğan, Tali̇p Güngör

Turkish Journal of Earth Sciences

In previous studies, the stratigraphy of the Menderes Massif was divided into a Precambrian core and Mesozoic cover associations, the core consisting of gneissic granites and high-grade schists and the cover of mica schists and platform-type marbles. It has also been proposed that the two associations are separated by an unconformity although nowhere is this relation clearly observed. In this study, the Bafa and Kavaklıdere areas in the southern part of the massif have been examined. In the Bafa area, Mesozoic mica schists with marble lenses occur in the lowermost parts of the sequence and are overlain, along a gradational …


Trace- And Rare-Earth Element Geochemistry Of The Karalar (Gazipaşa-Antalya) Barite-Galena Deposits, Southern Turkey, Gülcan Bozkaya, Ahmet Gökçe Jan 2004

Trace- And Rare-Earth Element Geochemistry Of The Karalar (Gazipaşa-Antalya) Barite-Galena Deposits, Southern Turkey, Gülcan Bozkaya, Ahmet Gökçe

Turkish Journal of Earth Sciences

The Karalar barite-galena deposits are typical examples of carbonate-hosted barite-galena deposits that occur widely in the central Taurides. Recent mining activity has been concentrated in the Büyük and Boyalık mine areas. The mineralisation occurs as ore veins along fault zones and as ore-filled breccia zones along the strongly deformed lower walls of limestone blocks in the Permian limestones of the Bıçkıcı Formation. These veins contain mainly barite (80-85%) and galena (10-15%), and lesser amounts of sphalerite, pyrite, fahlore, limonite, quartz and calcite as gangue minerals. Barite developed during an early episode of mineralisation and was mylonitised before the precipitation of …


Conjugacy Classes Of Finite Subgroups Of Certain Mapping Class Groups, Michal Stukow Jan 2004

Conjugacy Classes Of Finite Subgroups Of Certain Mapping Class Groups, Michal Stukow

Turkish Journal of Mathematics

We give a complete description of conjugacy classes of finite subgroups of the mapping class group of the sphere with r marked points. As a corollary we obtain a description of conjugacy classes of maximal finite subgroups of the hyperelliptic mapping class group. In particular, we prove that, for a fixed genus g, there are at most five such classes.


Moments Equalities For Nonnegative Integer-Valued Random Variables, Mohamed I. Riffi Jan 2004

Moments Equalities For Nonnegative Integer-Valued Random Variables, Mohamed I. Riffi

Turkish Journal of Mathematics

We present and prove two theorems about equalities for the nth moment of nonnegative integer-valued random variables. These equalities generalize the well known equality for the first moment of a nonnegative integer-valued random variable X in terms of its cumulative distribution function, or in terms of its tail distribution.


The Theory Of Jacobi Systems And Their Abelian Representations, M. Shahryari, Y. Zamani Jan 2004

The Theory Of Jacobi Systems And Their Abelian Representations, M. Shahryari, Y. Zamani

Turkish Journal of Mathematics

In this article we introduce a new generalization of the concept of Lie ring which we call Jacobi system and we investigate some elementary properties of these systems and their Abelian representations.


On \Theta-Euclidean L-Fuzzy Ideals Of Rings, Ayten Koç, Erol Balkanay Jan 2004

On \Theta-Euclidean L-Fuzzy Ideals Of Rings, Ayten Koç, Erol Balkanay

Turkish Journal of Mathematics

In this paper we define a \theta-Euclidean level subset and a \theta-Euclidean level ideal. We also give some properties of a \theta-Euclidean level subset.


On The Power Subgroups Of The Extended Modular Group \Gamma, Recep Şahi̇n, Sebahatti̇n İki̇kardeş, Özden Koruoğlu Jan 2004

On The Power Subgroups Of The Extended Modular Group \Gamma, Recep Şahi̇n, Sebahatti̇n İki̇kardeş, Özden Koruoğlu

Turkish Journal of Mathematics

In this paper we describe the group structure of power subgroups \Gamma^m of the extended modular group \Gamma and the quotients to them. Then we give some relations between the power subgroups \Gamma^m, the commutator subgroups \Gamma^{\prime} and \Gamma^{\prime \prime} and also the information of interest about free normal subgroups of the extended modular group \Gamma.


New Special Curves And Developable Surfaces, Shyuichi Izumiya, Nobuko Takeuchi Jan 2004

New Special Curves And Developable Surfaces, Shyuichi Izumiya, Nobuko Takeuchi

Turkish Journal of Mathematics

We define new special curves in Euclidean 3-space which we call slant helices and conical geodesic curves. Those notions are generalizations of the notion of cylindrical helices. One of the results in this paper gives a classification of special developable surfaces under the condition of the existence of such a special curve as a geodesic. As a result, we consider geometric invariants of space curves. By using these invariants, we can estimate the order of contact with those special curves for general space curves. All arguments in this paper are straight forward and classical. However, there have been no papers …


Modules Supplemented Relative To A Torsion Theory, M. Tamer Koşan, Abdullah Harmanci Jan 2004

Modules Supplemented Relative To A Torsion Theory, M. Tamer Koşan, Abdullah Harmanci

Turkish Journal of Mathematics

This article introduces the concept of a \tau-supplemented module as follows: Given a hereditary torsion theory in Mod R with associated torsion functor \tau, we say that a module M is \tau-supplemented when for every submodule N of M there exists a direct summand K of M such that K\leq N and N/K is \tau-torsion module. We present here some fundamental properties of this class of modules and study the decompositions of \tau-supplemented modules under certain conditions on modules. The question of which direct sum of \tau-supplemented R-modules are \tau-supplemented is treated here.


Groups With Rank Restrictions On Non-Subnormal Subgroups, Leonid Andreevich Kurdachenko, Howard Smith Jan 2004

Groups With Rank Restrictions On Non-Subnormal Subgroups, Leonid Andreevich Kurdachenko, Howard Smith

Turkish Journal of Mathematics

Let G be a group in which every non-subnormal subgroup has finite rank. This paper considers the question as to which extra conditions on such a group G ensure that G has all subgroups subnormal. For example, if G is torsion-free and locally soluble-by-finite then either G has finite 0-rank or G is nilpotent. Several results are obtained on soluble (respectively, locally soluble-by-finite) groups satisfying the stated hypothesis on subgroups.


On Orthogonal Generalized Derivations Of Semiprime Rings, Nurcan Argaç, Atsushi Nakajima, Emi̇ne Albaş Jan 2004

On Orthogonal Generalized Derivations Of Semiprime Rings, Nurcan Argaç, Atsushi Nakajima, Emi̇ne Albaş

Turkish Journal of Mathematics

In this paper, we present some results concerning two generalized derivations on a semiprime ring. These results are a generalization of results of M. Bre\u{s}ar and J. Vukman in [2], which are related to a theorem of E. Posner for the product of derivations on a prime ring.


On Near-Rings With Two-Sided \Alpha-Derivations, Nurcan Argaç Jan 2004

On Near-Rings With Two-Sided \Alpha-Derivations, Nurcan Argaç

Turkish Journal of Mathematics

In this paper, we introduce the notion of two-sided \alpha-derivation of a near-ring and give some generalizations of [1]. Let N be a near ring. An additive mapping f: N\rightarrow N is called an { \it (\alpha, \beta)-derivation } if there exist functions \alpha,\beta : N\rightarrow N such that f(xy)=f(x)\alpha(y)+\beta (x)f(y) for all x,y\in N. An additive mapping d:N\rightarrow N is called a two-sided \alpha-derivation if d is an (\alpha,1)-derivation as well as a (1,\alpha)-derivation. The purpose of this paper is to prove the following two assertions: (i) Let N be a semiprime near-ring, I be a subset of N …


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.


Ideal Theory In Topological Algebras, A. Najmi Jan 2004

Ideal Theory In Topological Algebras, A. Najmi

Turkish Journal of Mathematics

Given a simplicial topologically non radical algebra A, we characterize its topological radical, radA. If furthermore A is advertive, then radA coincides with the Jacobson radical RadA. On the other hand, it is shown that every two-sided invertive simplicial topological Gelfand-Mazur algebra has a functional spectrum and for every topologically nonradical simplicial Gelfand-Mazur amits the set \mathcal{X}(A), of all continuous multiplicative linear functionals, is not empty.


On Simultaneous Approximation By A Linear Combination Of A New Sequence Of Linear Positive Operators, P. N. Agrawal, Ali J. Mohammad Jan 2004

On Simultaneous Approximation By A Linear Combination Of A New Sequence Of Linear Positive Operators, P. N. Agrawal, Ali J. Mohammad

Turkish Journal of Mathematics

In [1] we introduced a new sequence of linear positive operators M_{n} to approximate unbounded continuous functions of exponential growth on [0,\infty). As this sequence is saturated with O(n^{-1}), to accelerate the rate of convergence we applied the technique of linear combination introduced by May [3] and Rathore et al. [4] to these operators. The object of the present paper is to study the phenomena of simultaneous approximation (approximation of derivatives of functions by the corresponding order derivatives of operators) by the linear combination M_{n} ( . , k, x) of M_{n}. First, we establish a Voronovskaja-type asymptotic formula and …


Coisotropic Submanifolds Of A Semi-Riemannian Manifold, Erol Kiliç, Bayram Şahi̇n, H. B. Karadağ, R. Güneş Jan 2004

Coisotropic Submanifolds Of A Semi-Riemannian Manifold, Erol Kiliç, Bayram Şahi̇n, H. B. Karadağ, R. Güneş

Turkish Journal of Mathematics

In this paper, we study coisotropic submanifolds of a semi-Riemannian manifold. We investigate the integrability condition of the screen distribution and give a necessary and sufficient condition on Ricci tensor of a coisotropic submanifold to be symmetric. Finally, we present some new theorems and results about totally umbilical coisotropic submanifolds of a semi-Riemannian manifold


F-Invariant Submanifolds Of Kaehlerian Product Manifold, Mehmet Atçeken Jan 2004

F-Invariant Submanifolds Of Kaehlerian Product Manifold, Mehmet Atçeken

Turkish Journal of Mathematics

In this paper, the geometry of F-invariant submanifolds of a Kaehlerian product manifold is studied. The fundamental properties of these submanifolds are investigated such as pseudo umbilical, curvature invariant, totally geodesic, mixed geodesic submanifold and locally decomposable Riemannian product manifold.


A Generalization Of A Result On Torsion-Free Groups With All Subgroups Subnormal, Tahi̇re Özen Jan 2004

A Generalization Of A Result On Torsion-Free Groups With All Subgroups Subnormal, Tahi̇re Özen

Turkish Journal of Mathematics

The main result in this paper is the following: Let G be a torsion-free locally nilpotent group and let F be a finitely generated subgroup of G. If every subgroup of G containing F is subnormal in G, then G is nilpotent.


On Local Hörmander-Beurling Spaces, Jairo Villegas Jan 2004

On Local Hörmander-Beurling Spaces, Jairo Villegas

Turkish Journal of Mathematics

In this paper we aim to extend a result of Hörmander's, that \mathcal{B}_{p,k}^{loc}(\Omega)\subset\mathcal{C}^m(\Omega) if \frac{(1+\left \cdot\right )^m}{k}\in L_{p^\prime}, to the setting of vector valued local Hörmander-Beurling spaces, as well as to show that the space \bigcap_{j=1}^\infty\mathcal{B}_{p_j,k_j}^{loc} (\Omega, E) (1\leq p_j\leq\infty, k_j=e^{j\omega}, j=1,2,\dots) is topologically isomorphic to \mathcal{E}_\omega(\Omega, E ). Moreover, it is well known that the union of Sobolev spaces \mathcal{H}_{s}^{loc}(\Omega) (=\mathcal{B}_{2,(1+ \cdot ^2)^{s/2}}^{loc}(\Omega)) coincides with the space \mathcal{D}^{\prime\,F}(\Omega) of finite order distributions on \Omega. We show that this is also verified in the context of vector valued Beurling ultradistributions.


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Zoology

No abstract provided.


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Physics

No abstract provided.


Self Ionization Probabilities Following De-Excitation Decay Of K-Shell Vacancy In Atoms Z = 10--80, Adel M. El-Shemi Jan 2004

Self Ionization Probabilities Following De-Excitation Decay Of K-Shell Vacancy In Atoms Z = 10--80, Adel M. El-Shemi

Turkish Journal of Physics

The average number of ejected electrons and the probability of ion charge state distributions following K-shell ionization in atoms from Z = 10 to Z = 80 were calculated. Monte Carlo simulation technique was used to simulate all possible pathways of radiative and non-radiative transitions to fill the inner-shell ionization in excited atoms. The radiative and non-radiative branching ratios were calculated from Multiconfiguration Dirac-Fock (MCDF) and Dirac-Fock-Slater (DFS) wave functions. The average number of ejected electrons in atoms with Z = 10 is about two, because the non-radiative transitions exceed radiative transitions by 98\%. The mean number of ejected electrons …


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Physics

No abstract provided.


Cyclotron Resonant Heating And Acceleration Of Protons, O Vi & Mg X Ions In The North Polar Coronal Hole, E. Rennan Pekünlü, Kadri̇ Yakut, Hi̇cran Şart Jan 2004

Cyclotron Resonant Heating And Acceleration Of Protons, O Vi & Mg X Ions In The North Polar Coronal Hole, E. Rennan Pekünlü, Kadri̇ Yakut, Hi̇cran Şart

Turkish Journal of Physics

Ultraviolet Coronograph Spectrometer aboard Solar and Heliospheric Observatory (SOHO) has revealed the existence of temperature anisotropy of many minor ion species that populate the north solar polar coronal hole. In this study, we examined the propagation characteristics of ion-cyclotron waves which resonate with protons, O VI and Mg X ions. In our empirical model, radial variation of the magnetic field, electron and ion number densities, perpendicular and parallel temperature of protons, O VI and Mg X ions are adopted from the measurements of various instruments aboard SOHO. Since most of the measurements of SOHO instruments begin at 1.5 R (=r/R_{\odot}) …


Calorimetric Studies Of The Crystallization Growth Process In Glassy Se_{70}Te_{30-X}Ag_X Alloys, N. Mehta, D. Kumar, A. Kumar Jan 2004

Calorimetric Studies Of The Crystallization Growth Process In Glassy Se_{70}Te_{30-X}Ag_X Alloys, N. Mehta, D. Kumar, A. Kumar

Turkish Journal of Physics

Differential Scanning Calorimetry (DSC) is performed at different heating rates under non-isothermal conditions to study the crystallization kinetics of Se_{.70}Te_{.26}Ag_{.04} and Se_{.70}Te_{.24}Ag_{.06} chalcogenide glasses in terms of the activation energy of nucleation and growth process. To understand the nucleation and growth process, the values of the growth morphology parameter n and the numerical factor m of crystallization mechanism have been evaluated using different non--isothermal methods. The values of n and m have been found to be nearly equal, indicating that the present glasses have sufficient nuclei before DSC experiment and the activation energy for nucleation process E_N is zero. Hence, …


Neural Analysis Of Top Shielded Multilayered Coplanar Waveguides, Mustafa Türkmen, Celal Yildiz, Şeref Sağiroğlu Jan 2004

Neural Analysis Of Top Shielded Multilayered Coplanar Waveguides, Mustafa Türkmen, Celal Yildiz, Şeref Sağiroğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Artificial neural networks (ANNs) have been promising tools for many applications. In recent years, a computer-aided design approach based on (ANNs) has been introduced to microwave modelling, simulation and optimization. In this work, the characteristic parameters of top shielded multilayered coplanar waveguides (CPWs) have been determined with the use of ANN models. These neural models were trained with Levenberg-Marquardt, resilient propagation, Bayesian regulation, quasi-Newton, and backpropagation learning algorithms. Better performance and learning speed with a simpler structure were achieved from these models. The results have shown that the estimated characteristic parameters are in very good agreement with the computed results …